Sludge removing system



Nov. 6, 1951 H. w. HAPMAN SLUDGE REMOVING SYSTEM 5 Sheets-Sheet 1 Filed Nov. 20, 1946 INVENTOR. 7y Zfl. flap/r700 MW 1951 H w. HAPMAN SLUDGE REMOVING SYSTEM 3 Sheets-Sheet 2 Filed Nov. 20, 1946 3 Sheets-Sheet 3 H, W. HAPMAN Nov. 6, 1951.

SLUDGE REMOVING SYSTEM Filed Nov. 20, 1946 Patented Nov. 6, 1951 UNITED STATES PATENT OFFICE 7 2,573,905 SLUDGE REMOVING SYSTEM Henry Hapman, Detroit, Mich, assign'or, by mesne assignments, of forty per cent to Hannah J. Hapman, Detroit, Mich. Application November 20, 1946, Serial No. 711,071

2 Claims.

, 1 I This invention relates to systems and devices for removing sludge from liquids. One object of this invention is to provide a system for removing sludge from a liquid circulating in a feeder conduit leading to a settling tank, wherein the feeder conduit is arranged to have the same liquid level as the settling tank and mechanism is provided for pickingup the sludge settling in the feeder conduit and conveying it to a suitable disposal receptacle, thereby adding the capacity of the feeder conduit to the capacity of the settling tank and reducing the size otherwise necessary for the settling tank.

Another object is to provide a system for removing sludge from a liquid, 'as set forth in the preceding object, wherein the conveying mecha nism also moves through the settling tank, to remove the sludge deposited therein and convey it to the disposal receptacle.

Another object is to provide a system for removing sludge from a liquid, as set forth in the preceding objects, wherein filtering devices are arranged in the settling tank to further purify the liquid therein from which the sludge is settling out. i

Another object is to provide a system for removing sludge from a liquid as set forth the preceding objects, wherein the conveyor consists of an endlessfiight conveyor which moves slowly through the bottom ofthe feeder conduit so as to pick up the sludge therein, and which thereafter preferably moves also through the settling tank to additionally pick up the remaining sludge settling out of the liquid flowing to the settling tank from the feeder conduit.

Another object is to provide a system ferremoving sludge from a liquid, wherein the settling tank is spaced on a floor below the machines which are served by the feeder conduit.

Another object isv to provide a system for removing sludge from a liquid circulating in a feeder conduit adjacent one floor or level of a building to a settling tank located 'on a floor or level below that of the feeder conduit whereby the sludge settling in the feeder conduit is removed therefrom by means of a flight conveyor passing therethrough while the'liquid which is thereby partially freed; froin the sludge flows down to the settling tank located on the level or floor below the feeder conduit.

Another object is toprovidea system for removing sludge from a liquid, asset forth inthe object immediately preceding, wherein the sludge settling in the settling is removed by atonveyor moving through the settling tank and is lie: posited in a suitable disposal receptacle.

Other objects and advantages of the invention will become apparent during the course of the following description of the accompanying drawings, wherein:

a Figure 1 is a diagrammatic top plan view of a sludge removal system, according to a preferred form of the invention, wherein the settling tank and feeder conduit are located on substantially the same level; v v V Figure 2 is a vertical section through the sludge removal system shown in Figure 1, taken substantially along the axis of the flight conveyor inov ing through the system;

Figure 3 is a vertical cross-section through the settling tank shown in Figures 1 and 2, taken along the line 3 -3 in Figure 2; p

Figure 4 is a vertical cross-section through the feeder conduit taken along the line 4 4 in Fig ure 2;

Figure 5 is a vertical longitudinal section through the feeder conduit, taken along the line 5-5 in Figure 4;

Figure 6 a vertical longitudinal section through the flight conveyor conduit at the bottom of the settling tank, taken along the line 6-6 in Figures;

Figure 7 is a diagrammatic top plan view of a modified sludge remeoval system, wherein the settling tank is located on a floor or level a con siderable distance below the feeder conduit;

I Figure 8 is a diagrammatic side elevation, partly in section, of the modified sludge removal sysitem shown in Figure "I;

Figure 9 is 'a vertical cross-section taken along 'the'line 9-9 in Figure 8, showing the flight conveyor for removing the sludge from the feeder conduit; and

Figure 10 is an enlarged vertical cross-section along the line Iill0 in Figure 7, showing the connection of the liquid returnrconduit to the feeder conduit and the conveyor therein.

In prior sludge removalsystems, it has been customary to collect the sludge in small sumps or in steamy-pitched feeder conduits and to pump it quickly and rapidly to a settling tank before the sludge has an opportunity tosettle but of the liquid to'any great extent. Such systems, when. used for removing metallic particles from a coolant liquid, however, have been subject to the disadvantage that the sludge settles rapidly in the feeder conduits despite vigorous efforts to remove it rapidly. Under such circumstances, it has been necessary to shovel outth sludge from the feeder conduits at intervals in order to prevent clogging of the system; It has also been necessary to provide an exceptionally large settling tank and filtering devices of high capacity to remove the sludge from the liquid in the settling tank. The result has been that the expense of such an installation has been excesconduits of prior systems. is also a very dirty.

task, especially in summertime, and is accompanied by the creation of offensive odors. The cost of providing and maintaining the pumps for pumping the liquid has also been excessive prior installations, since it has been necessary to pump the sludge along with the liquid before it settles out.

In the sludge removal system of the present invention, these disadvantages are eliminated by deliberately providing for the settling out of sludge not only in the settling tank but also in the feeder conduits, and providing a flight conveyor system which will remove the sludge from the feeder conduits as rapidly as it settles in the conduits. The feeder conduits are preferably placed on the same level'with the upper portion of the settling tank, so that thesame liquid level is maintained in both, thereby adding the liquid capacity of the feeder conduits to that of the settling tank. This enables the settling tank itself to be made of much smaller capacity than in prior installations, where the settling tank had to accomplish substantially the entire task of sludge removal.

Furthermore, since a portion of the sludge is removed from the liquid while it is stillflowin through the feeder conduits, much less sludge remains in the liquid when it reaches the settling tank than in prior installations-thereby requirsystem are located on the same level. The sludge removal system I 0 consists generally of a settling and filtering unit I l and a feeder conduit system I2, the latter being divided into tributary conduits I3 leading from individual machines or sources of sludgecontaining liquid (not shown) to a main sludge-contaminated liquid collection conduit I4. A typical installation consists of a number of machine tools, such as grinding machines employing a coolant liquid, the liquid after use flowing through the tributary conduits I3 into the main conduit It. The conduits I3 and I4 may be tubular or may consist of open trenches of concrete, steel or other suitable material. The tributary conduits I3 are preferably as short as possible and steeply pitched so that the liquid containing the sludge flows as quickly as possible into the main conduit I l before seting a smaller filtering capacity for the filtering devices in the tank. In this way; both the first cost and maintenance cost of the present system is considerably less than those of prior installations, offensive odors are eliminated or g'reatly reduced, and the manual removal of sludge from the feeder conduits is done away with. Since the combined volume of the feeder conduits and the settling tank of the present invention is larger than the capacity of prior settlingtanks alone, for similar conditions, the liquid circulates more slowly and hence is cooler when it reaches the settling tank. The formation of bacteria is thus retarded as compared with previous installations and spoilage is reduced, thereby enabling the liquid to be used for a longer period of time than in prior installations.

Moreover, since the present'invention accomplishes a part of the settling out of the sludge in the feeder conduits, the liquid reaching the settling tank contains much less sludge and convsequently, a smaller filtering installation is necessary as compared with prior sludge removal systems. The first cost and upkeep cost of the system is therefore still further reduced by the present system.

Single-level sludge removal system Referring to the drawings in detail, Figures 1 to 6 inclusive show a sludge removal system, generally designated I0, according to the present invention, where the component parts lithe tling takes place. i

The main conduit I4 contains an endless flight conveyor unit generally designated l5 for removing the sludge which settles out therein. The endless conveyor also' preferably passes through the sludge tank It which forms a part of the settling and filtering unit I! so that a single flight conveyor unit I5 serves both the main conduit I4 and sludge tank I6. From Fi ure 2 it will be seen that the main conduit I4 is of greater length but shallower than the settling tank. The sludge tank It and main conduit I4 are so arranged (Figure 2) that the level of the top of the liquid I1 is the same in both, so that the capacity of the main conduit I4 is added to that of the settling tank I6 for settling purposes. The main conduit I4 may be of any suitable length and path, either straight or zigzag, depending upon the nature of the machine layout which it serves. In order to serve a layout containing a number of machines as shown in Figure 1, the collection conduit I4 has a length exceeding the length of said tank, and is disposed on a level with the upper portion of said tank, as shown in Figure'Z. For purposes of illustration (Figure 1) the main conduit I4 has been shown as a straight trench into which the tributary conduits I3 feed at right angles, but any arrangement thereof may be made, according to the conditions encountered.

The main conduit I4 (Figure-4) into which the tributary conduits I3 feed, when consisting of a concrete trench, may be provided with a recess or groove I8 at the bottom thereof for receiving the lower course of the flight conveyor unit I5. The latter is preferably made removable. When so constructed, it may consist of upper and lower channel members I9 and 20 respectively for carrying the upper and lower courses 2| and 22 of the flight conveyor, generally designated 23 which forms the conveying portion of the flight conveyor unit I5. The channel members I9 and 2!] are interconnected by uprights 24 (Figure 4) welded or otherwise secured thereto. The lower channel member 20 rests in the groove I8 and the upper channel member I9 and uprights 24 are provided with side angle members 25 welded or otherwise secured thereto at intervals. The side members 25 prevent the conveyor unit I5 from tipping over and their outer ends rest against the vertical side walls of the main conduit I4 for this purpose. The conveyor unit I5, however, may be removed from the main conduit I4 merely by removing the cover member 26 (Figure 4) which is preferably a grating resting upon the angle members 21 at the top of the main conduit l4. 7

28 having'outer and inner links '29 and 30 respectively interconnected by pivot pins 31. Secured to the chain 28 are the bent ends '32 of semi-circularclamping plates 33 between which are clamped disc-like flights 34 of rubber or rubber-like material, as by the fasteners 35 (Figures 4 and The flights 34 are arranged to one side (of the chain 28 rather than symmetrically thereon. The chain 28 at its end passes over sprockets 36 and 31 (Figures 1 and .2) at the-opposite ends of its run, atleastdne-df these. sprockets being driven by any suitable source of power (not shown). As disclosed in my above-mentioned .co-pending application Serial No. 676,546., filed June 13, 1946, the flights 34 and clamping plates 33 are loosely connected to the links and by providing enlarged holes and excessive clearances for the fasteners and pivot pins 3!. Accordingly, during operation, as a'resultof these loose fits, the conveyor chain twists longitudinally as it traverses bends in the conveyor conduit or passes around sprockets, so that the weight of the chain causes it to rest on the hot- I tom of the conveyor conduit on both its upper and lower courses, as shown inFigure '5, with the flights 34 extending upward.

At the point where the conveyor 23 approaches the settling tank IE, it enters a tubular conduit 38 and the portion returning from the settling tank it emerges from a tubular return conduit 39, these .being bell-mouthed to facilitate passage of the conveyor 23. The tubular conduit 38 passes downward to the bottom of'the settling tank 16 and runs along the bottom thereof through openings 40 in partitions 4| before ascending atthe opposite side of the settling tank 16. 'Along the bottom run, the tubular conduit 33 is cut away as at 42 (Figures 2v and 6) so as to permit the sludge settling out in the tank It to enter the conduit 38 and be conveyed onward hy the conveyor 23. The side walls 43 of the settling tank I6 are inclined toward one another (Figure 3) so as to facilitate the descent of the sludge towardthe conduit 38. The en lwalls 44 may be vertical and the end wa'l1.45 inclined (Figure 2) so as to facilitate the entrance and the emergence of the conduit 38.

Extending betwen the partitions 4| in the settling tank I6 are I-beams 45 which serve to support the inner ends of swinging pipes 41 and 43 (Figure 3) which in turn support filtering devices'49. The latter are conventional and their details form no part of the present invention.

The filtering devices 49 are staggered in their arrangement within the tanks; so that thepipes 4'! are longer than the pipes 48. Both pipes, however, are connected at their outer ends to rotatable conduits, 50.- Bythis construction, the pipes 47 and 48 and their filtering devices 43maybe swung upward above the liquid level Hand out of the. settling tank l6 for cleaning or servicing, as shown by the dotted lines in Figure 3 l The portion of the settling tank l6 adjacent the inclined end wall 45' is provided with a pump enclosure 5| which contains pumps 52 driven by motors 53 (Figure 1). The pump enclosure 5! is, of course, dry and sealed oil from the remainder of the settling tank I 6 so that liquid cannot enter except through the pipes 50, which are connected to the pumps 52. The discharge pipe 5'4 is connected to the outlets of the pumps 52 and leads to the machines or other devices utilizing the filtered liquid. In order to carry away the sludge removed from the liquid by settling in the main conduit [4 and settling tank IB, asludge bucket or car 56 maybe placed beneath the sprocket 31 (Figures 1 and 2) at the upper ends of the conduits '38 and 33.

Opera-nanny single-level sludge removal system the main conduit M. The liquid moves slowly along the conduit 14 since it has the same liquid level i? as the sludge tank "I6, fiow taking place as the pumps 52 remove liquid from the settling tank after it has been filtered by the filtering devices 453, and it is returned to the machines through the liquid discharge pipe '54.

As the liquid moves slowly along the main conduit [4 toward the settling tank 16, the heavier portions of the sludge therein settle to the bottom of the conduit 14. Any sludge settling in the portion of the main conduit l4 immediately adjacent the sludge tank 16, after the flight conveyor 23 enters the conduit 38, is removed by providing openings (not shown) in the latter similar to the openings 42 (Figures 2 and 6). As the flight conveyor 23 moves through the main conduit I4, its lower course 22 picks up the sludge at the bottom of the conduit and conveys it into the conduit 38 and thence downward into the settling tank l6 and along the bottom thereof. As the conveyor 23 passes through the bottom portion of the conduit 38, it also takes up the sludge which has settled in the bottom of the settling tank l6 and which has passed through the holes 42. The conveyor 23 picks up this additional sludge, along with the sludge which it has already picked up in the main conduit I4, and carries it upward out of the settling tank l6 along the inclined end wall 45 (Figure '2) and discharges it into the sludge bucket or car 56. V

The return course 2| of the flight conveyor 23, after passing around the drive sprocket 31, traverses the conduit 39 and emerges into the upper portion of the main conduit I 4, moving along the channel member l9 until it reaches the sprocket 36. It then passes downward around the latter and moves along the channel member 20 in the groove 18 completing its cycle and again commencing to pick up and convey sludge in a newcycle.

Meanwhile, the liquid, which has been freed from the heavier portions of its sludge as it passes through the portions of the main conduit I4, reaches the settling tank It and is subjected to the action of the filtering devices 49. The filtered liquid is then Withdrawn from the settling tank It through the filtering devices 49 by means of a pump 52 and discharged through the pipe 54 to the machine. The speed of the conveyor23 is adjusted so that it moves rapidly enough to have some reserve capacity for sludge remaining when it enters the settling tank It after picking up the sludge which has settled in the main conduit [4.

Multiple-level sludge removal system The modified sludge. removal system, generally designated 60 shown in Figures 7 to 10 inclusive follows the same general principles. as the single level system Ill shown in Figures 1 to 6 inclusive,

air- 2 5 except that it is intended to servemachines or other sources of sludge-bearing liquid which are located on floors or levels above the settling tank. It is inconvenient to mount settling tanks above the ground level, except in buildings especially constructed to sustain the great weight thereof and for such installations, the modified system of Figures 7 to 10 inclusive has been devised. For purposes of simplification the system is shown in these figures as applied to an installation one floor above the settling tank, but it will be obvious that it can equally well serve several floors, if desired.

The multiple level system 60 is provided with a settling tank 6| sunk below the level of the ground floor 62, whereas the machines or. other sludge-producing devices are located on an upper floor 63. The settling tank 61 has inclined side walls 63 similar to the side walls 43 of the settling tank IS in Figure 3, and is similarly provided with filtering devices, which are omitted for purposes of simplification. A loop-like bent conduit 64 or similar construction to the conduit 38 and containing a flight conveyor 65 similar to the flight conveyor 23, traverses the conduit 64 which is provided with openings (not shown) similar to the openings 42 for admitting sludge. The flight conveyor 65 is provided with a drive sprocket 68 connected to a suitable source of power (not shown) and discharges its sludge into a sludge bucket or car 61.

The machines or othersludge producing units on the upper floor 63 are provided with tributary conduits 68 leading downward through the floor 63 to a loop-like main conduit 99 of tubular form supported in any suitable way such as by brackets (not shown) secured to the underside of the floor 63. A flight conveyor 10 similar to the flight conveyor 23 of Figures 1 to 6 inclusive traverses the main conduit 69 and emerges at the top of its upwardly inclined ends H and 12 to pass around a drive sprocket 73 connected to a suitable source of power (not shown). Beneath this is arranged a sludge bucket or car E4.

The major portion of the main conduit 69 is in the form of a horizontal loop and near the 10- cation where its end portions H and 12 start to incline upward is provided with openings 15 and 16 (Figure 10) to which is connected a liquid discharge conduit 11. The latter is likewise supported in any suitable way, such as from the underside of the floor 63, and extends downward into the settling tank 0| sunk below the floor 62.

Operation of multiple-level sludge removing system The operation of the multiple level sludge removal system 60 (Figures 7 to 10 inclusive) is similar in principle to that of the single level system (Figures 1 to 6 inclusive). The sludge producing devices, such as machines, discharge their sludge containing liquid through the tributary conduits 68 intothe main conduit 69, where settling of the heavier particles of sludge takes place in a manner similar to that occurring in the main conduit M as previously described. The main conduit 69 is of considerably larger diameter than the flights of the flight conveyor 10 which traverses it, hence the flight conveyor 10 moves slowly along the bottom of the conduit 69 until it climbs the inclined portion H and arrives at the sludge bucket or car '14, dumping the sludge which it has collected into the latter. The liquid which has been freed from its heavier sludge by the settling occurring in the main conduit 69, passes through the opening 15 in the upper side of the conduit portion H, and enters the return conduit 11, theliquid level 18 in which is slightly above the top of the conduit 69, (Figure' 10). r

The liquid containing the lighter particles of sludge moves downward through the conduit 11 into the settling tank 6| where the remaining particles of sludge are either settled out and removed by the flight conveyor 65 in the conduit 64 or by the filtering devices ,(not shown) in the tank Bl, similar to those previously described and shown in connection with the settling tank IS. The sludge settling to the bottom of the settling tank 6| along the inclined bottom walls 63 thereof and picked up by the flight conveyor 65 in the conduit 64 is discharged into the sludge bucket or car 61 and removed.

What I claim is: V V

1. A sludge collection and removal apparatus comprising a sludgesettling tank, a sludge-contaminated liquid collection conduit disposed externally of saidtank on a level with the upper portion of said tank and having a length exceeding the length of said tank, said collection conduit extending from a sludge-collecting location remote from said tank to aconnection with said tank, a sludge discharge conduit extending upwardly out of saidtank to a sludge disposal station disposed externally of said tank, and a single endless flight conveyor mounted in said conduits and tank and extending through said collection conduit downwardly through the lower portion of said tank and upwardly through said discharge conduit to said sludge disposal station and returning to said collection conduit.

2. A sludge collection and removal-apparatus comprising a sludge settling tank, a sludge-contaminated liquid collection conduit disposed externally of said tank on a level with the upper portion of said tank and having a length exceeding the length of said tank, said collection conduit extending .from a sludge-collecting location remote from said tank to a connection with said tank on one side of said tank, a sludge discharge conduit extending upwardly out of said tank onanother side of said tank to a sludge disposal station disposed externally of said tank, and. a single endless flight conveyor .mounted in said conduits and tank. and extending through said collection conduit downwardlythrough the lower portion of said tank and upwardly through said discharge conduit to said sludge disposal station and returning to said collection conduit.

HENRY W. HAPMAN.

REFERENCES CITED The following references are of record in the file of this-patent: 

1. A SLUDGE COLLECTION AND REMOVAL APPARATUS COMPRISING A SLUDGE SETTLING TANK, A SLUDGE-CONTAMINATED LIQUID COLLECTION CONDUIT DISPOSED EXTERNALLY OF SAID TANK OF LEVEL WITH THE UPPER PORTION OF SAID TANK AND HAVING A LENGTH EXCEEDING THE LENGTH OF SAID TANK, SAID COLLECTION CONDUIT EXTENDING FROM A SLUDGE-COLLECTING LOCATION REMOTE FROM SAID TANK TO A CONNECTION WITH SAID TANK, A SLUDGE DISCHARGE CONDUIT EXTENDING UPWARDLY OUT OF SAID TANK TO A SLUDGE DISPOSAL STATION DISPOSED EXTERNALLY OF SAID TANK, AND A SINGLE ENDLESS FLIGHT CONVEYOR MOUNTED IN SAID CONDUITS AND TANK AND EXTENDING THROUGH SAID COLLECTION CONDUIT DOWNWARDLY THROUGH THE LOWER PORTION OF SAID TANK AND UPWARDLY THROUGH SAID DISCHARGE CONDUIT TO SAID SLUDGE DISPOSAL STATION AND RETURNING TO SAID COLLECTION CONDUIT. 